Screen printing apparatus



July 2, '1940. R. F. FOARD SCREEN PRINTING APPARATUS Filed March 15, .1939 2 Sheets-Sheet. 1

11v VENTOR g 05597 fi. Fan/e0 3 ATTORNEY \1 Fla Patented July 2, 1 940 UNITEDZSTATES PATENT orrics Robert F. Foard,Los Angeles, Calif. Application March 13, 1939, Serial No. 261,584

9 Claims.

My invention relates to screen printing apparatus adapted for multiple color printing on cloth and among the objects of myinvention are:

First, to provide a multiple color screen printing apparatus whereby particularly accurate registry of the different colors may be readily obtained.

Second, to provide an apparatus of this character which is economical of floor space, the apparatus occupying very little more than twice the area of the material upon which it is capable of printing.

Third, to provide an apparatusof this character which is equally applicable to printing on cut or partially finished articles such as towels, napkins, table cloths etc.; or to printing on yardage or piece goods in webs or bolts.

Fourth, to provide an apparatus of this character wherein the time requirement in order to apply selected number of colors is reduced to a minimum.

Fifth, to'provide an apparatus of this character wherein blended or secondary colors, that is, colors derived from superposed applications of different primary colors may be obtained, by reason of the rapidity of application as well as the accuracy of registry obtained.

Sixth, to provide a simple and novel means for registering the several screens of a multiple color set of screens may be placed upon the goods to be printed in sequence with assurance that the registry once obtained will be maintained.

With the above and other objects in view as may appear hereinafter, reference is directed to the accompanying drawings in which:

Figure l is a perspective view of my apparatus.

Figure 2 is a longitudinal sectional view thereof taken substantially through 2-2 of Fig. 1 with one printing frame structure shown partially extended and parts and portions shown in elevation to facilitate the illustration.

Figure 3 is a fragmentary plan view of the printing frame and printing table as-they appear when in position for printing. I

view thereof taken through i-4 of Fig. 3.

My multiple color screen printing apparatus comprises essentially of a carriage structure I adapted to contain a plurality of screen printing frame structures 2 which are capable of being selected and placed one at a time upon a printing table 3.

The carriage structurecomprises a housing H of rectangular form and having side walls i2, and a bottom it. The bottom of the housing ii is suitably mounted on an elevator M which may comprise a plunger I5 and cylinder 55a adapted to be actuated by fluid pressure from a suitable source not shown, to raise and lower the housing ll. Suitable uprights it may guide the housing Figure 4 is an enlarged fragmentary sectionalso that it remains level and is restrained to a vertical movement.

Thesides I 2 of the housing ll are provided with tracks I! having a plurality of rollers l8.

Also additional rollers i9 may be on the side walls 5 above each track. The tracks are arranged in pairs, each pair adapted to guide and support a screen printing framestructure 2. i

Each screen printing frame structure comprise an outer frame 2! preferably-formed of angle from the printing table to the corresponding track as will be described in more detail hereinafter.

Within the outer frame 2| is an inner frame 23 which constitutes the printing frame proper. The frame 23 preferably made of wood and is in most respects similar to conventional screen printing frames. The inner or printing frame 23 defines an opening covered by a conventional printing screen 24 of fine grade silk or the like which is treated in such a manner that it is impervious except for those areas, through which it is desired to force dye or ink.

The printing frames 23 fit loosely in their outer frames 2| and are secured therein by adjustable wedges or quoins 25 positioned adjacent each corner. Adjustment of the quoins permit adjustment of the printing screen relative to the outer frame to facilitate registry as will be described in more detail hereinafter.

One set of outer frames may be used for several sets of printing frames 23, consequently, in

ill

of approximate registry so that further adjustment by means of the quoins is facilitated.

The table 3 includes a table top it suitably supported at working height on legs and having a relieved area slightly in excess of the area of a printing frame structure. This area is adapted to receive one of several work holding plates 32 depending on the size and shape of the article to be screen printed. If for example, four articles such as napkins, towels, handkerchiefs or the like are to be printed, four platen faces 33 are provided. Each platen face is defined by channels 34 which connect with each other. extending along the sides from front to rear of the plate extend rearwardlybeyond the platen faces to the rear edge of the work holding plate as indicated by 35.

Work is positioned over the platen faces so that its margins extend into the channels 34 and are held therein by a clamping frame 36 which is complementary to said channels including arms 31 which extend to the rear edge of the plate and are connected therewith by hinges 38. In addition the front edge of the clamping frame 36 is provided with a hinged handle 39 adapted to hook over the forward edge of the plate and be used to assist in raising the clamping frame.

.Both' the clamping frame and normal surfaces of the plate 32 including the platen faces 33 are covered with a cushion 40 of uniform thickness.

If a single article is to be printed, the work holding plate is provided with a single platen face the size and shape of which is dependent up the article-in question. It is not necessary.

. tha the cloth material be cut to size before thereon at a time. each cam elevator 22 and at the rear edgev of the I printing for yardage may be fed in steps across the table and either one or several prints made More particularly, adjacent to'p 3| of the table 3 are provided coacting brackets 4i and 42 including semi-circular,

rearwardly directed lip portions 43 and 44 respectively. The lip portion 43 of the bracket 4| associated with the frame structure 2 is provided with a centered aperture 45 and a depending skirt 46; while the lip portion 44 of the other bracket is provided with an upstanding pin 41 adapted to fit the aperture 45.

To facilitate lateral positioning of the frame structure 2, upstanding guide members 418 may be positioned for engagement with the sides of the cam elevators 22-. v

In addition, to two such coacting brackets at the two rear corners of the frame structure, another set of registering fittings may be provided at one or both outer corners of the frame stru'c-- ture 2.

Thus, brackets 5| and 52 are secured to the frame 2| and table top 3| and are provided with semi-circular lip portions 53 and 54 respectively. The lip portion 53 is providedwith a depending pin 55 adapted to fit an aperture in the other lip portion 54, and the lip portion 54 is provided with an upstandingsemi-circular guide wall 56.

In order to facilitate removal of the selected frame structure 2 from the carriage I, an ejector is provided which includes a plunger 6|,

mounted at the proper height in rear of the carriage and adapted to engage the rear edge of the frame structure positioned in proper relation to the table 3. The plunger 6| is actuated by a.

lever 82 below the forward side of the table 3 in an accessible position for the operator. A suitable spring, not shown, tends to hold the plunger in a retracted position.

Movement of the plunger is so adjusted that the frame structure is moved only part way out of the carriage so that the forward edge of the frame structure may be grasped by the operator and, withdrawn the remaining distance. To

facilitate return of the frame structures, the

several tracks are on a slight slope downwardly toward the rear of the carriage.

Movement of the carriage may be controlled by a suitable valve II which connects the cylinbe raised, lowered or stopped.

To facilitate proper positioning of the carriage with respect to the table a stop arm 12 which is r hinged to one of the uprights I6 and engages Operation of my screen printing apparatus is as follows:

Assuming that four articles are to be printed simultaneously; for example, napkins; these are laid over the platen faces 33 of the plate 32 printing frame structure 2 on a level slightly.

above the table 3. The frame structure is withdrawn, with the assistance of the ejector, the operator holding the front end of the frame structure clear of the work, while the track maintains the rear end of the frame structure clear. The position assumed by the frame structure during such movement is best shown by dotted lines in Fig. 2.

While the front end of the frame structure is heldin an elevated position, the cam elevators 22 allow the rear end of the frame structure to descend; The skirts 46 of brackets 4| engage the lips 44 of brackets 42 and guide the pins 41 into place. Sufficient distance is provided between the rear edge of the frame structure and the working area of the screens to insure clearance until the pins 41 are in place. The front end of the frame structure in predetermined registry with the work.

It should be noted that the printing screens 24 are normally spaced upwardly slightlyfrom the work; and are forced down into contact with the work by a squeege in a conventional manner.

After one color has been applied, the frame structure is returned by first raising the front end until the entire printing screen 24 is clear.

This brings the rear end of the elevator cam 22 into engagement with the front' rollers of the corresponding track whereby the frame structure may be readily returned to the carriage.

The carriage is raised or lowered to position screens is easily obtained.

Trial prints are made with theprinting screens and each printing screen frame adjusted in its outer frame by means of the quoins 25'until the desired registry is obtained between the different printing screens when the outer frames are held by the coacting fittings between the frame structures 2 and table 3. ,By use of the spacers 26, it is possible to establish the approximate position of the printing frames 23 so that if it is desired to remove the printing frames so as to print other designs, the printing frames may be replaced without material adjustment.

Though I have shown and described a particular embodiment of my invention, I do not wish to be limited thereto but desire to include in the scope of my invention the constructions,-

on each of said frame structures and table whereby said frame structures may be set interchangeably on said table in predetermined rela-' tion therewith; a screen printing frame for each frame structure; adjustable spacer means interposed between each printing frame and its frame structurefor adjusting the printing frame into a position. (if registry over said table corresponding to the registry of the other printing frames and their frame structures when interchange on said table and fixed spacers fitted between each printing frame and its frame structure upon initial adjustment of said adjustable spacers whereby said printing frame may be removed from its frame structure and replaced therein in approximately registry position to minimize readjustment of said adjustable spacer means.

2. An apparatus for screen printing on cloth comprising: a table having work receiving platen faces and recesses bordering said platen faces;

a clamping frame hinged to said table and adapted to flt in saidrecesses' to hold the marginal portions of cloth overlaying said platen faces, the surfaces of said clamping frame being substantially flush with said platen faces; coasting fittings on each of said frame structures and table whereby said frame structures may be set interchangeably on said table in predetermined relation therewith; a screen printing frame for each frame structure; adjustable spacer means interposed bctween each printing frame and its frame structure for adjusting the printing frame into a position of registry over said table corresponding to the registry of the other printing frames and their frame structures when interchanged on said table. a

3. A-structure as set forth in claim 2 wherein fixed spacers approximating the adjusted spacing of said adjustable spacer means are attached to said printing framesafter said printing frames have been adjusted into registry, whereby said printing frames may be removed and re-inserted in said frame structures and occupy approximately positions of registry without adjustment.

4. An apparatus for screen printing on cloth comprising: a table; means for securing thereon 'cloth to be printed; a carriage structure at one side of said table adapted to be raised and low- 'ered; a plurality of screen printing frame structures carried by said carriage and each adapted to be withdrawn therefrom to a position over said table when said carriage is in predetermined relation therewith; and coasting fittings carried,

printing frame structures adapted to receivethe same in superposed, spaced relation; and means for moving. said holder to positions whereby a selected frame structure is slightly above the level of the table, whereupon the frame structure may be withdrawn without contact with the "table until said fittings are in position for coaction. 6. An apparatus as set forth in claim 5 wherein brackets extend from said frame structures into engagement with said holder to formfuicrum points whereby saidframe structures may be moved substantially vertically away from the cloth retained by said securing means.

7. A screen printing apparatus comprising: a"

table having recesses therein adapted to receive the marginal portions of cloth-to be printed; clamp means adapted to fit in said recesses to hold the cloth in position; registering elements on saidtable; a plurality of screen printing frame structures, each including an outer frame having registering means coacting with said registering elements, an inner frame, means for adjusting and fixing the position of the inner frame with respect to the outer frame, and a printing screen secured to said inner fre; means for supporting said screen printing frame structures in superposed relation on one side of said table; and means for moving said supporting means into positions whereby a selected frame structure may be moved over said table.

8. A screen printing apparatuscomprising; a

table having recesses therein adapted, to receivethe marginal portions of cloth to be printed; clamp means adapted to fit in said recesses to hold the cloth in position; registering elements on said table; a plurality of screen printing frame structures, each including an outer frame having registering means coacting with said registering elements; an inner frame, means for adjusting and fixing the positibn of the inner frame with respect to the outer frame, and a printing screen secured to said inner frame; a carriage for supporting said screen printing frame structures insuperposed relation at one side of said table, said carriage including tracks to facilitate withdrawal of said frame structures; means for shifting said carriage to positions whereby a selected frame structure is positioned slightly above the level of said table; and coacting devices on said frame structure and said tracks whereby when a selected frame structure is substantiallywithdrawn therefrom said frame structure may be moved substantially vertically to or from said table.

9. A screen printing apparatus comprising: a

table having recesses therein adapted to receive the marginal portions of cloth to be printed; clamp means adapted to fit in said recesses to hold the cloth in position; registe elements on said tablefa plurality of screen printing frame structures, each including an outer frame having registering means coacting with said registering elements; an inner frame, means for adjusting and fixing the position of the inner fre with respect to the outer frame, and a printing screen secured to said inner frame; means for supporting said screen printing frame structures in superposed relation on one" side of said tabie;

means for moving said supporting cans into positions whereby a selected frame structure may be moved over said table; and an ejector engageable withthe selected frame structure for 

